/*  */
.fullscreen-layout {
  position: relative;
  width: 400px;
  height: 400px;
}

header,
footer,
main {
  position: absolute;
  left: 0;
  right: 0;
}

header {
  top: 0;
  height: 50px;
  background-color: #f66;
}

footer {
  bottom: 0;
  height: 50px;
  background-color: #66f;
}

main {
  top: 50px;
  bottom: 50px;
  background-color: #3c9;
}